From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 30809 invoked by alias); 25 Jun 2014 22:03:27 -0000 Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org Received: (qmail 30797 invoked by uid 89); 25 Jun 2014 22:03:26 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-3.0 required=5.0 tests=AWL,BAYES_00 autolearn=ham version=3.3.2 X-HELO: mx2.suse.de Received: from cantor2.suse.de (HELO mx2.suse.de) (195.135.220.15) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (CAMELLIA256-SHA encrypted) ESMTPS; Wed, 25 Jun 2014 22:03:25 +0000 Received: from relay1.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 5C50BAC7E; Wed, 25 Jun 2014 22:03:22 +0000 (UTC) Date: Wed, 25 Jun 2014 22:03:00 -0000 From: Martin Jambor To: Jeff Law Cc: Bernd Edlinger , Richard Biener , "gcc-patches@gcc.gnu.org" Subject: Re: [PATCH] Change default for --param allow-...-data-races to off Message-ID: <20140625220321.GA18164@virgil.suse> Mail-Followup-To: Jeff Law , Bernd Edlinger , Richard Biener , "gcc-patches@gcc.gnu.org" References: <20140620114418.GB24436@virgil.suse> <20140624201933.GB32150@virgil.suse> <53AB3BB7.7020603@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <53AB3BB7.7020603@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-IsSubscribed: yes X-SW-Source: 2014-06/txt/msg02073.txt.bz2 Hi, On Wed, Jun 25, 2014 at 03:14:31PM -0600, Jeff Law wrote: > On 06/24/14 14:19, Martin Jambor wrote: > >On Mon, Jun 23, 2014 at 03:35:01PM +0200, Bernd Edlinger wrote: > >>Hi Martin, > >> > >>>> > >>>>Well actually, I am not sure if we ever wanted to have a race condition here. > >>>>Have you seen any impact of --param allow-store-data-races on any benchmark? > >>> > >>>It's trivially to write one. The only pass that checks the param is > >>>tree loop invariant motion and it does that when it applies store-motion. > >>>Register pressure increase is increased by a factor of two. > >>> > >>>So I'd agree that we might want to disable this again for -Ofast. > >>> > >>>As nothing tests for the PACKED variants nor for the LOAD variant > >>>I'd rather remove those. Claiming we don't create races for those > >>>when you disable it via the param is simply not true. > >>> > >>>Thanks, > >>>Richard. > >>> > >> > >>OK, please go ahead with your patch. > > > >Perhaps not unsurprisingly, the patch is very similar. Bootstrapped > >and tested on x86_64-linux. OK for trunk? > > > >Thanks, > > > >Martin > > > > > >2014-06-24 Martin Jambor > > > > * params.def (PARAM_ALLOW_LOAD_DATA_RACES) > > (PARAM_ALLOW_PACKED_LOAD_DATA_RACES) > > (PARAM_ALLOW_PACKED_STORE_DATA_RACES): Removed. > > (PARAM_ALLOW_STORE_DATA_RACES): Set default to zero. > > * opts.c (default_options_optimization): Set > > PARAM_ALLOW_STORE_DATA_RACES to one at -Ofast. > > * doc/invoke.texi (allow-load-data-races) > > (allow-packed-load-data-races, allow-packed-store-data-races): > > Removed. > > (allow-store-data-races): Document the new default. > > > >testsuite/ > > * g++.dg/simulate-thread/bitfields-2.C: Remove allow-load-data-races > > parameter. > > * g++.dg/simulate-thread/bitfields.C: Likewise. > > * gcc.dg/simulate-thread/strict-align-global.c: Remove > > allow-packed-store-data-races parameter. > > * gcc.dg/simulate-thread/subfields.c: Likewise. > > * gcc.dg/tree-ssa/20050314-1.c: Set parameter allow-store-data-races > > to one. > Don't we want to deprecate, not remove the dead options? > Is there a mechanism for deprecating parameters (I could not quickly find any) or do you mean to leave them there and only document them as deprecated? I am not really concerned how we deal with the unused parameters, removing or any form of deprecating is fine with me. Thanks, Martin